Bottle closure



1957 YONENDO TAKAHASHI ETAL ,8

BOTTLE CLOSURE Filed Dec. 50. 1955 INVENTORS. YONE/VDO TAKAHASHI,

YUK/CH/ TANA/(A M WW'MW A T TORNE X United States Patent BO'ITLE CLOSURE Yonendo Takahashi, Nakano-Ku, and Yukichi Tanaka, Toshima-Ku, Tokyo, Japan, assignors to American Cyanamitl Company, New York, N. Y., a corporation of Maine Application December 30, 1955, Serial No. 556,661

1 Claim. (Cl. 215-41) This invention relates to a bottle closure and more particularly to a combination stopper and cap type closure for medicinal products.

For many products, particularly medicinal products, it is desirable to have a closure for a bottle which is easily opened, easily closed, moisture-proof, and particularly, proof against accidental dislodging.

For purposes of convenience the containers will be spoken of as bottles, although they are sometimes classified as vials, or ampules, or jars.

A particular illustration is shown for a small bottle although it will be readily understood the side may vary with the requirements of the packaged product.

The bottle is equipped with a lip and over the neck of the bottle including the lip is placed the closure.

The particular closure of this invention can be best illustrated by reference to the accompanying drawings. These drawings show two embodiments:

Figure 1 is a partial sectional view of a bottle with the present novel closure for larger size bottles.

Figure 2 is a bottom view of the closure of Figure 1.

Figure 3 is a view of a closure for smaller size bottles.

Figure 4 shows the bending induced in the closure by pressure within the bottle.

The present closure is constructed of a moldable, synthetic resin which is flexible and firm. Particularly, polyethylene or a polyvinylchloride may be used. It is essential that the material of the closure be flexible in order that the pressures developed within the vial may cause deflection of the closure in such fashion as to more firmly retain the closure in position.

As shown in Figure 1 a bottle 11 has a neck 12 which on its upper portion has a bottle lip 13. As shown in Figure 1 the lip has a closing cam surface 14, and a retaining cam surface 15. The closing cam surface 14 is frusto-conical in general shape so that the closure slides up and over when being placed on the bottle. The underside of the lip forming the retaining cam surface is also generally frusto-conical in configuration, but in an inverse direction so that the cone of the retaining cam surface 15 is pointed towards the bottom of the bottle.

The present closure consists of a single piece of the molded resin, which is preferably polyethylene. A slightly bulged top disk 16 forms the central part of the closure and bulges upward away from the bottle. Surrounding the top disk is a substantially cylindrical hollow inner stem 17 which has a bevel 18 on its lower portion to aid in insertion in a bottle. The stem itself is either cylindrical or slightly tapered towards the lower end. Surrounding the top disk and inner stem is an annular ring 19 which supports a skirt 20 which is also cylindrical in configuration and extends downward from the top surface of the closure. In the configuration shown in Figures 1 and 2 the upper surface of the skirt has vertical corrugations 21 therein to aid in holding the closure, and to prevent the hand of the user from slipping during application or removal. The outside of the skirt also has a lift tab 22 to aid in removing the closure. Slight pressure under the lift tab will start one edge of the closure sliding off, and make it easy to remove the closure. Inside the skirt is an inner head 23. The inner head as shown in Figure 1 may be partway up the skirt portion, and as shown in Figure 1 consist of a small bead raised on the interior surface of the cylindrical skirt. This bead is such a distance from the annular ring that when the bottle is capped the bead engages the retaining cam surface 14 on the bottle which causes the closure to be pulled downward onto the bottle. A 30 to 60 degree angle of contact gives excellent results. Preferably there is a small bead 27 on the exterior face of the closure at the bottom to give added stifiness, and avoid tearing or rupture.

The thickness of the parts is important. It is desirable to keep the weight of pharmaceutical containers and their closures at a minimum, and as polyethylene is a fairly expensive material it is desired to use as little of it as is consistent with a good closure. Fortunately, the closure of the present invention is one in which thin walls are not only feasible but desirable. The essence of the entire closure is in having walls which are thin enough to readily flex, and to utilize the stresses which are induced to cause the closure to become more firmly emplaced. In other words, whereas in the average closure, pressures within the bottle must be resisted, with the present closure any pressures within the bottle are actually an advantage. For example, on a closure on a bottle which is approximately 1 inches high, and inch in diameter, the entire closure may be made with a top disk, and inner stem, and an outer skirt which is approximately ,4, inch thick, although the top disk and annular ring may be 50% thicker than the inner stem and skirt. The inner stem is slightly larger than the interior neck of the bottle so when forced into position the stem is slightly compressed. This has two functions (1) the friction between the stem and the bottle is greater because of the compression, and any pressures Within the bottle will tend to force the stem out against the neck of the bottle thereby retaining it in position; (2) additionally, as the stem is compressed it causes the slightly bulged top disk to bulge further which increases the pressure on the stem, and causes the top disk as it flexes to cause a reverse flexure to the annular ring which in turn tends to contact the skirt, and causes the inner bead to contract inwardly, and bear more firmly on the neck on the bottle. As shown in Figure 4, the internal pressure acts at A to cause the stem to frictionally engage the inside neck of the bottle, and also pressure at B causes the annular disk to rotate outwardly as shown at C which causes the bead to press more firmly against the closing cam surface 14.

Polyethylene is sufliciently flexible that the closure may he slipped over the neck of the bottle, and the inner bead cams over the closing cam surface 14 into position, and the hoop tension induced in the skirt pulls the inner bead 23 underneath the retaining cam surface, and thereby retains the stopper in position. Obviously, the skirt and bead must be sufliciently flexible that they can cam over the bottle lip, and also must be of such thickness that the force required for the camming action is within the range of force conveniently excrtable by the person who removes or replaces the closure. Fortunately, with polyethylene, in a thickness of approximately & inch, all of these limitations are met, and a moisture-proof, easily replaceable, easily removable closure is provided. With softer or harder polyethylene, and various bottle sizes. the thickness will vary.

In the modification shown in Figure 3 which is designed particularly for smaller bottles, the inner bead rather than being placed intermediate of the skirt, is at the bottom of the skirt 25. An exterior head 26 reinforces the inner bead and gives additional stiffness to the lower edge of the skirt so as to prevent tearing. The closure shown in Figure 3 may be from inch to 1 inch in thickness and yet retain the desirable characteristics of easy removal and firm closure.

The forces within the bottle are used to retain the closure. In many instances the actual emplacement of a closure traps air and causes a build-up in pressure, and in other cases gas is given off from the contents, or expansion caused by warming the bottle and its contents builds up a pressure within the bottle. As above described these pressurcs actually do more to retain the closure in position than to remove it, and it is actually at least as difficult or even more difficult to remove the closure from the bottle when there is a pressure therein, than when the pressure is approximately the same as external pressure. This is a new development in closures which thus permits the use of lighter materials and more economical cross-sections.

We claim:

A homogeneous plastic closure of stilf resilient resin from the group consisting of polyethylene and polyvinyl chloride for a bottle comprising: a slightly bulged top disk, a hollow inner stem dependent therefrom, a bevel at the lower end of said stem, of such direction and slope as to aid in the insertion of the closure in a bottle, an

annular ring surrounding the top disk and inner stem, a dependent exterior skirt shorter than the inner stem; a bead interiorly of said skirt part by way up the interior face of said skirt, in such position as to cam against a closing cam surface of the bottle lip of a bottle to be closed with a 30 to 60 angle of contact; an exterior bead surrounding and integral with the lower edge of said skirt and reinforcing said skirt; vertical corrugations all the way around the dependent exterior skirt, joining the exterior bead, and extending to the top of the exterior skirt; and a lifting tab formed by an outward flaring portion of the exterior head; the top disk, the inner stem, and the corrugation reinforced skirt all being of such thickness that pressures within a closed bottle cause the more firm emplacement of the closure on the bottle.

References Cited in the file of this patent UNITED STATES PATENTS 20 2,586,775 Benner et al. Feb. 26, 1952 FOREIGN PATENTS 278,533 Switzerland Jan. 16, 1952 1,013,553 France Apr. 30, 1952 1,030,600 France Mar. 18. 1953 

